The present invention relates to analog signals sampling and, more particularly, to method and corresponding device for sampling at least one analog signal and providing digital representation thereof, featuring an analog circuit integrated with a control unit, wherein the control unit is keeping error outputs of the system at a minimal value. The control unit is using discrete value signals that are digitally feed to a DSP that is reconstructing the at least one analog input signal.
The present invention is primarily directed to applications requiring high bandwidth with low current consumption, including but not limited to applications of signal processing of analog sources in a variety of applications such as radar, imaging and analog front-end of wireless modem, including those using direct RF sampling.
The inputs to a previous art sampler are analog signal(s) and a clock or any other deterministic signal or signals. Previous art sampler is a system containing linear components, non-linear components, amplifiers, and optionally, delay elements and decision elements that output bits as function of its input, such as comparators or small analog to digital converters of 2 bits. The previous art sampler is designed to provide accurate conversion of each analog sample to its digital equivalent. Occasionally, the previous art sampler is calibrated in order to compensate for the inaccuracy of its components. More specifically, the gains and offsets of the previous art sampler are modified in order to achieve digital representation of the sampled analog signals featuring better accuracy. Alternatively, the previous art sampler includes calibration of its output in the digital domain.
Prior art samplers are described by models featuring multiple stages, wherein each stage in the model is independent from all other stages. In other words, models of prior art samplers are an aggregation of multiple models of each stage. Each stage in the model refers to specific voltage or current value that is measured in a specific time frame. Each stage treats the specific value it receives as an input and provides its result to the next stage. Moreover, prior art stage is not dependent on previous values.